How can I get rid of this?

[poppy]

Hi I was rendering cloth, and I got this boxy, polygony stuff on my mesh.

I was a triangulated plane, Mantra surface color, no maps, PBR renderer. Tried poly as subdivide in render option. Tried subdivide the mesh, but doesn't help.

[dennis.albus]

Are you using anisotropy in your reflections? If your mesh doesn't have uv's applied the parametric attributes s and t might get used which might lead to a look like yours. Maybe you could upload your scene file so we can have a look at it.

-dennis

[poppy]

Thanks Dennis

Here my scene file

cloth03.hip

[dennis.albus]

I took a look at your file and indeed anisotropy was the reason for the artifacts.

What I did to fix this is:

- I added UVs to the cloth before it gets simulated by DOPs

- I copied the UVs back to the simulated geometry (not quite sure why I had to do this, because I thought my UVs would be piped through DOPs)

- changed the tangent style parameter on the Surface Model VOP inside your cloth material from "Geometric Tangents" to "Compute from UV"

I marked the nodes that I added and/or changed with red.

-dennis

[Erik_JE]

I am curious why the UVs need to be copied back and don't stick. Anyone knows?

[dennis.albus]

Sorry, forgot to attach the file.

cloth03_fix.hip

[poppy]

Thanks again Dennis

Being a TD always be my dream goal, but still, it's a long way to go

(and,btw, I really love We Can Dance vimeo channel)

one quick question tho

what this do?

- changed the tangent style parameter on the Surface Model VOP inside your cloth material from "Geometric Tangents" to "Compute from UV"

Edited October 26, 2011 by poppy